Elementos de transposição: diversidade, evolução, aplicações e impacto nos genomas dos seres vivos / Transposable elements: diversity, evolution, applications and impact in the genomes of living beings

Este livro representa um projeto desafiador: o estudo de sequências genéticas repetidas que são capazes de se mover, tornando os genomas dinâmicos e flexíveis. Os elementos de transposição (TEs) têm a capacidade de se multiplicar e mudar de lugar no genoma, levar consigo genes, promover rearranjos cromossômicos e alterar a expressão de genes vizinhos. Trata-se de um dos tópicos mais instigantes na área da genética, que durante décadas não recebeu o devido reconhecimento. O livro surgiu de uma reunião de integrantes do grupo de pesquisa Elementos de Transposição como Agentes de Diversidade, do CNPq, que consideram indispensável disponibilizar a pesquisadores e estudantes informações que permitam compreender a dinâmica e a plasticidade dos genomas em decorrência da presença dos TEs. O livro não esgota as inúmeras informações e implicações decorrentes da interação genoma-TE mas propicia aos leitores o contato atualizado e a compreensão dos principais temas relacionados à estrutura e funcionamento dessas sequências genéticas móveis e sua relação com a evolução dos organismos, afirmam as organizadoras...

Xylella fastidiosa comparative genomic database is an information resource to explore the annotation, genomic features, and biology of different strains

The Xylella fastidiosa comparative genomic database is a scientific resource with the aim to provide a user-friendly interface for accessing high-quality manually curated genomic annotation and comparative sequence analysis, as well as for identifying and mapping prophage-like elements, a marked feature of Xylella genomes. Here we describe a database and tools for exploring the biology of this important plant pathogen. The hallmarks of this database are the high quality genomic annotation, the functional and comparative genomic analysis and the identification and mapping of prophage-like elements. It is available from web site http://www.xylella.lncc.br.

Combined genotypic-phenotypic phylogeny of the tribe Spathicarpeae (Araceae) with reference to independent events of invasion to Andean regions.

The Neotropical tribe Spathicarpeae is noteworthy within the family Araceae for having members occurring in very dry and/or very high (above 3000m) areas in South America. Considering the small size of previously included genera in the tribe (10 geophytic genera, none with more than 15 described species), generic circumscription has been considered troublesome. To address these issues, we sequenced two cpDNA markers (matK and trnL-F) and reconstructed the phylogeny of the tribe using two approaches: Maximum parsimony and Bayesian Inference. We also evaluated the effect of adding phenotypic characters in a "total evidence" analysis. Our results confirm the previous suggestion that the two non-geophytic genera Dieffenbachia and Bognera should be included in Spathicarpeae, but the precise placement of Bognera within the tribe is still unresolved. Our results also support the segregation of Asterostigma pavonii and Asterostigma integrifolium, recently described as new monospecific genera (Incarum and Croatiella, respectively). The reconstructed phylogenies suggest that the invasion of the Andean range by the Spathicarpeae occurred in at least two independent events. The inclusion of phenotypic characters in a combined analysis has improved both internal resolution and the number of strongly supported clades.